Belgian-American physicist wins Nobel for work on ‘ghostly messengers’

Belgian-American physicist Francis Halzen yesterday won the Nobel physics prize for groundbreaking work using South Pole ice to capture particles originating in the distant cosmos, providing insight into the far reaches of space.

“This year’s prize is about ghostly messengers from space,” Royal Swedish Academy of Sciences secretary-general Ellen Moons told a news conference.

Halzen was honored “for decisive contributions to the IceCube Neutrino Observatory and the discovery of high-energy neutrinos of astrophysical origin,” the jury said.

Belgian-American particle physicist Francis Halzen speaks in Alexandria, Virginia, on July 12, 2018, about his work to detect neutrinos in Antarctica.

Photo: Reuters

Halzen’s work had been fundamental for the observatory, which consists of a cubic kilometer of ice that is equipped with light sensors, and had “paved the way for a new kind of astronomy,” the Royal Swedish Academy of Sciences said.

Using the observatory, researchers can capture neutrinos — rare subatomic particles — “from extremely energy-rich processes in the distant universe.”

Halzen, 82, was born in Tienen, Belgium, and is a professor at the University of Wisconsin-Madison in the US.

“It was a great surprise, and I obviously didn’t expect it,” he told the news conference by telephone shortly after the prize was announced.

“But it’s a great pleasure to hear about this prize,” he added.

The academy said that high-energy neutrinos are created in the same environments as other particles.

“However, unlike other particles, neutrinos reach us without changing direction or losing energy. This means they can provide information that is not available in any other way,” it said in a statement.

Halzen first presented his idea for the observatory in 1988 and his idea quickly gained the support of other researchers.

Preliminary testing was conducted just a few years later, but the observatory was not completed until 2011.

“Cosmic neutrinos with extremely high energies are very rare, so an enormous volume of ice is needed to observe an adequate number of collisions,” the jury said.

“For me, the main pleasure of it, besides winning the Nobel Prize, is that I hope this reflects on the really courageous people who joined me in the beginning of this project,” Halzen said.

Asked whether neutrinos could even contain messages from potential distant civilizations, Halzen said that “it has been speculated that ... this would be an ideal way to communicate with aliens.”

“But I don’t think I will go there. I think we have enough realistic problems to deal with right now,” he said.